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Administration of ORNL Research Reactors (open access)

Administration of ORNL Research Reactors

Organization of the ORNL Operations division for administration of the Oak Ridge Research Reactor, the Low Intensity Testing Reactor, and the Oak Ridge Graphite Reactor is described. (J.R.D.)
Date: August 20, 1962
Creator: Casto, W. R.
Object Type: Report
System: The UNT Digital Library
Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report (open access)

Leaching study of PNL 76-68 glass beads using the LLNL continuous-flow method and the PNL-modified IAEA method. Final report

Lawrence Livermore National Laboratory (LLNL) has conducted a long-term single-pass continuous-flow (SPCF) leaching test of the glass waste form PNL 76-68. Leaching rates of Np, Pu, and various stable elements were measured at 25/sup 0/ and 75/sup 0/C with three different solutions and three different flow rates. The purposes of the study were: (1) to compare SPCF leaching results with the results of a modified IAEA leach test performed by Pacific Northwest Laboratories (PNL); (2) to establish elemental leach rates and their variation with temperature, flow rate and solution composition; and (3) to gain insight into the leaching mechanisms. The LLNL and PNL leach tests yielded results which appear to agree within experimental uncertainties. The magnitude of the leach rates determined for Np and the glass matrix elements is 10/sup -5/ grams of glass/cm/sup 2/ geometric solid surface area/day. The rates increase with temperature and with solution flow rate, and are similar in brine and distilled water but higher in a bicarbonate solution. Other cations exhibit somewhat different behavior, and Pu in particular yields a much lower apparent leach rate, probably because of sorption or precipitation effects after release from the glass matrix. After the initial few days, most elements …
Date: August 20, 1982
Creator: Buddemeier, R. W.; Coles, D. G.; Mensing, R. W.; Rego, J. & Weed, H. C.
Object Type: Report
System: The UNT Digital Library
GENERAL STANDARDS GUIDE FOR EXPERIMENTS IN ORNL RESEARCH REACTORS (open access)

GENERAL STANDARDS GUIDE FOR EXPERIMENTS IN ORNL RESEARCH REACTORS

The Oak Ridge National Laboratory has three generalpurpose research reactors which accommodate testing loops, target irradiations, and beam-type experiments. Since the experiments must share common or similar facilities and utilities, be designed and fabricated by the same groups, and meet the safe safety criteria, certain standards for these have been developed. These standards deal only with those properties from which safety and economy of time and money can be maximized and do not relate to the intent of the experiment or quality of the data obtained. The necessity for, and the limitations of, the standards are discussed; and a compilation of general standards is included. (auth)
Date: August 20, 1962
Creator: Cagle, C.D.
Object Type: Report
System: The UNT Digital Library
Evaluation of anion exchange resins for processing plutonium--neptunium residues (open access)

Evaluation of anion exchange resins for processing plutonium--neptunium residues

An anion exchange process was developed to process miscellaneous residues of plutonium plus 0.5 wt % neptunium to allow prompt return of the plutonium to a plutonium recovery process. Several macroreticular anion exchange resins were compared to Dowex 1-X4 for the process. Dowex 1-X4 showed the best performance for the plutonium (III)-neptunium(IV) separation.
Date: August 20, 1977
Creator: Navratil, J. D. & Leebl, R. G.
Object Type: Report
System: The UNT Digital Library
AI-MSG modification work plan. [LMFBR] (open access)

AI-MSG modification work plan. [LMFBR]

This document contains the Work Plan for the modification of the AI Steam Generator for tests in Large Leak Test Rig. This Work Plan describes the objectives, scope of work, schedule and manpower, end items, and meetings and reports required for the modification.
Date: August 20, 1973
Creator: Page, J.P.
Object Type: Report
System: The UNT Digital Library
Neutron Production of Charm Particles in Fermilab E-400 (open access)

Neutron Production of Charm Particles in Fermilab E-400

Results are presented from Fermilab E-400 on the production of charmed baryons and mesons using incident neutrons. We show evidence for the charm-strange baryon, ..xi../sub c//sup +/, and present our measurements of its mass, width, lifetime, cross section and relative branching fractions, and the A, x/sub f/, p/sub t/, and particle/antiparticle dependence of the state. We show evidence for both the ..sigma../sub c//sup + +/ and ..sigma../sub c//sup 0/, and present measurements of three mass differences, ..sigma../sub c//sup + +/ - ..sigma../sub c//sup 0/, ..sigma../sub c//sup 0/ - ..lambda../sub c//sup +/, and ..sigma../sub c//sup + +/ - ..lambda../sub c//sup +/. Preliminary results on the ratio of two decay modes of the D/sup 0/ are shown. D/sup 0/ ..-->.. K/sup +/K/sup -/ and D/sup 0/ ..-->.. K/sub 0/ anti K/sub 0/. The latter mode has not been previously observed. 8 refs., 10 figs.
Date: August 20, 1987
Creator: Cumalat, J. P.; Binkley, M.; Bossi, F.; Butler, J.; Coteus, P.; DiCorato, M. et al.
Object Type: Article
System: The UNT Digital Library
National waste terminal storage program (open access)

National waste terminal storage program

Papers are presented on research programs concerned with underground storage of radioactive wastes. A separate abstract was prepared for each of twenty-three papers. (JRD)
Date: August 20, 1977
Creator: unknown
Object Type: Article
System: The UNT Digital Library
Commissioning of the LCLS Linac and Bunch Compressors (open access)

Commissioning of the LCLS Linac and Bunch Compressors

The Linac Coherent Light Source (LCLS) is a SASE x-ray Free-Electron Laser (FEL) project under construction at SLAC [1]. The injector section, from drive-laser and RF photocathode gun through the first bunch compressor, was commissioned in the spring and summer of 2007. The second phase of commissioning, including the second bunch compressor and various main linac modifications, was completed in January through August of 2008. We report here on experience gained during this second phase of machine commissioning, including the injector, the first and second bunch compressor stages, the linac up to 14 GeV, and beam stability measurements. The final commissioning phase, including the undulator and the long transport line from the linac, is set to begin in December 2008, with first light expected in July 2009.
Date: August 20, 2008
Creator: Akre, R.; Brachmann, A.; Decker, F.-J.; Ding, Y.; Dowell, D.; Emma#, P. et al.
Object Type: Article
System: The UNT Digital Library
Testing Short Samples of ITER Conductors and Projection of Their Performance in ITER Magnets (open access)

Testing Short Samples of ITER Conductors and Projection of Their Performance in ITER Magnets

Qualification of the ITER conductor is absolutely necessary. Testing large scale conductors is expensive and time consuming. To test straight 3-4m long samples in a bore of a split solenoid is a relatively economical way in comparison with fabrication of a coil to be tested in a bore of a background field solenoid. However, testing short sample may give ambiguous results due to different constraints in current redistribution in the cable or other end effects which are not present in the large magnet. This paper discusses processes taking place in the ITER conductor, conditions when conductor performance could be distorted and possible signal processing to deduce behavior of ITER conductors in ITER magnets from the test data.
Date: August 20, 2007
Creator: Martovetsky, N. N.
Object Type: Article
System: The UNT Digital Library
Measurement of Branching Fractions and CP and Isospin Asymmetries of B -> K* g (open access)

Measurement of Branching Fractions and CP and Isospin Asymmetries of B -> K* g

We present a preliminary analysis of the decays B{sup 0} {yields} K*{sup 0}{gamma} and B{sup +} {yields} K*{sup +}{gamma} using a sample of 383 million B{bar B} events collected with the BABAR detector at the PEP-II asymmetric energy B factory. We measure the branching fractions {Beta}(B{sup 0} {yields} K*{sup 0}{gamma}) = (4.58 {+-} 0.10 {+-} 0.16) x 10{sup -5} and {Beta}(B{sup +} {yields} K*{sup +}{gamma}) = (4.73 {+-} 0.15 {+-} 0.17) x 10{sup -5}. We measure the direct CP asymmetry to be -0.043 < {Alpha}(B {yields} K*{gamma}) < 0.025 and the isospin asymmetry to be -0.021 < {Delta}{sub 0-} < 0.079, where the limits are determined at the 90% confidence interval and include both the statistical and systematic uncertainties.
Date: August 20, 2008
Creator: Yarritu, A.
Object Type: Article
System: The UNT Digital Library
2007 Molecular & Cellular Bioenergetics (June 17-22, 2007) (open access)

2007 Molecular & Cellular Bioenergetics (June 17-22, 2007)

This Report describes Molecular & Cellular Bioenergetics.
Date: August 20, 2008
Creator: Fevzi Daldal, Nancy Ryan Gray
Object Type: Article
System: The UNT Digital Library
Update of Time-Dependent CP Asymmetry Measurements in b to c-cbar-s Decays (open access)

Update of Time-Dependent CP Asymmetry Measurements in b to c-cbar-s Decays

We present updated measurements of time-dependent CP asymmetries in fully reconstructed neutral B decays containing a charmonium meson. The measurements reported here use a data sample of (465 {+-} 5) x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II B factory. The time-dependent CP asymmetry parameters measured from J/{psi}K{sub S}{sup 0}, J/{psi}K{sub L}{sup 0}, {psi}(2S)K{sub S}{sup 0}, {chi}{sub c1}K{sub S}{sup 0}, {eta}{sub c}K{sub S}{sup 0}, and J/{psi}K*{sup 0} decays are: (1) C{sub f} = 0.026 {+-} 0.020(stat) {+-} 0.016(syst); and (2) S{sub f} = 0.691 {+-} 0.029(stat) {+-} 0.014(syst).
Date: August 20, 2008
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
A fourth order accurate adaptive mesh refinement method forpoisson's equation (open access)

A fourth order accurate adaptive mesh refinement method forpoisson's equation

We present a block-structured adaptive mesh refinement (AMR) method for computing solutions to Poisson's equation in two and three dimensions. It is based on a conservative, finite-volume formulation of the classical Mehrstellen methods. This is combined with finite volume AMR discretizations to obtain a method that is fourth-order accurate in solution error, and with easily verifiable solvability conditions for Neumann and periodic boundary conditions.
Date: August 20, 2004
Creator: Barad, Michael & Colella, Phillip
Object Type: Article
System: The UNT Digital Library
Comparative study of Ti and Ni clusters from first principles (open access)

Comparative study of Ti and Ni clusters from first principles

Icosahedral clusters in Ti and Ni are studied with first-principles density functional calculations. We find significant distortion on the Ti icosahedron caused by the strong interaction between surface atoms on the icosahedron but not between the center atom and surface atoms, whereas no such distortion is observed on Ni clusters. In addition, distortion becomes more severe when atoms are added to the Ti13 cluster resulting in short bonds. Such distorted icosahedra having short bonds are essentially to explain the structure factor of Ti liquid obtained in experiment.
Date: August 20, 2007
Creator: Lee, B & Lee, G W
Object Type: Article
System: The UNT Digital Library
A Comparison of Photoresist Resolution Metrics using 193 nm and EUV Lithography (open access)

A Comparison of Photoresist Resolution Metrics using 193 nm and EUV Lithography

Image blur due to chemical amplification represents a fundamental limit to photoresist performance and manifests itself in many aspects of lithographic performance. Substantial progress has been made in linking image blur with simple resolution metrics using EUV lithography. In this presentation, they examine performance of 193 nm resist and EUV resist systems using modulation transfer function, corner rounding, and other resolution metrics. In particular, they focus on cross-comparisons in which selected EUV and 193 nm resist are evaluated using both EUV and 193 nm lithography. Simulation methods linking 193 nm and EUV performance will be described as well. Results from simulation indicate that image blur in current generation 193 nm photoresists is comparable to that of many EUV resists, but that ultra-low diffusion materials designs used in very high resolution EUV resists can result in substantially lower blur. In addition to detailing correlations between EUV and 193 nm experimental methods, they discuss their utility in assessing performance needs of future generation photoresists.
Date: August 20, 2007
Creator: Jones, Juanita; Pathak, Piyush; Wallow, Thomas; LaFontaine, Bruno; Deng, Yunfei; Kim, Ryoung-han et al.
Object Type: Article
System: The UNT Digital Library
2006 Savannah River Site Annual Illness and Injury Surveillance Report (open access)

2006 Savannah River Site Annual Illness and Injury Surveillance Report

The U.S. Department of Energy’s (DOE) commitment to assuring the health and safety of its workers includes the conduct of illness and injury surveillance activities that provide an early warning system to detect health problems among workers. The Illness and Injury Surveillance Program monitors illnesses and health conditions that result in an absence, occupational injuries and illnesses, and disabilities and deaths among current workers.
Date: August 20, 2008
Creator: United States. Department of Energy. Office of Health, Safety, and Security.
Object Type: Report
System: The UNT Digital Library
Firewall Architectures for High-Speed Networks: Final Report (open access)

Firewall Architectures for High-Speed Networks: Final Report

Firewalls are a key component for securing networks that are vital to government agencies and private industry. They enforce a security policy by inspecting and filtering traffic arriving or departing from a secure network. While performing these critical security operations, firewalls must act transparent to legitimate users, with little or no effect on the perceived network performance (QoS). Packets must be inspected and compared against increasingly complex rule sets and tables, which is a time-consuming process. As a result, current firewall systems can introduce significant delays and are unable to maintain QoS guarantees. Furthermore, firewalls are susceptible to Denial of Service (DoS) attacks that merely overload/saturate the firewall with illegitimate traffic. Current firewall technology only offers a short-term solution that is not scalable; therefore, the \textbf{objective of this DOE project was to develop new firewall optimization techniques and architectures} that meet these important challenges. Firewall optimization concerns decreasing the number of comparisons required per packet, which reduces processing time and delay. This is done by reorganizing policy rules via special sorting techniques that maintain the original policy integrity. This research is important since it applies to current and future firewall systems. Another method for increasing firewall performance is with new …
Date: August 20, 2007
Creator: Fulp, Errin W.
Object Type: Report
System: The UNT Digital Library
Optimization of the cooling profile to achieve crack-free Yb:S-FAP crystals (open access)

Optimization of the cooling profile to achieve crack-free Yb:S-FAP crystals

Yb:S-FAP [Yb{sup 3+}:Sr{sub 5}(PO{sub 4}){sub 3}F] crystals are an important gain medium for diode-pumped laser applications. Growth of 7.0 cm diameter Yb:S-FAP crystals utilizing the Czochralski (CZ) method from SrF{sub 2}-rich melts often encounter cracks during the post growth cool down stage. To suppress cracking during cool down, a numerical simulation of the growth system was used to understand the correlation between the furnace power during cool down and the radial temperature differences within the crystal. The critical radial temperature difference, above which the crystal cracks, has been determined by benchmarking the simulation results against experimental observations. Based on this comparison, an optimal three-stage ramp-down profile was implemented and produced high quality, crack-free Yb:S-FAP crystals.
Date: August 20, 2007
Creator: Fang, H; Qiu, S; Kheng, L; Schaffers, K; Tassano, J; Caird, J et al.
Object Type: Article
System: The UNT Digital Library
MMA, A Computer Code for Multi-Model Analysis (open access)

MMA, A Computer Code for Multi-Model Analysis

This report documents the Multi-Model Analysis (MMA) computer code. MMA can be used to evaluate results from alternative models of a single system using the same set of observations for all models. As long as the observations, the observation weighting, and system being represented are the same, the models can differ in nearly any way imaginable. For example, they may include different processes, different simulation software, different temporal definitions (for example, steady-state and transient models could be considered), and so on. The multiple models need to be calibrated by nonlinear regression. Calibration of the individual models needs to be completed before application of MMA. MMA can be used to rank models and calculate posterior model probabilities. These can be used to (1) determine the relative importance of the characteristics embodied in the alternative models, (2) calculate model-averaged parameter estimates and predictions, and (3) quantify the uncertainty of parameter estimates and predictions in a way that integrates the variations represented by the alternative models. There is a lack of consensus on what model analysis methods are best, so MMA provides four default methods. Two are based on Kullback-Leibler information, and use the AIC (Akaike Information Criterion) or AICc (second-order-bias-corrected AIC) model …
Date: August 20, 2007
Creator: Hill, Eileen P. Poeter and Mary C.
Object Type: Report
System: The UNT Digital Library
Evidence for CP violation in B0 to J/Psi pi0 Decays (open access)

Evidence for CP violation in B0 to J/Psi pi0 Decays

None
Date: August 20, 2008
Creator: Aubert, B.; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
Modeling Leaking Gas Plume Migration (open access)

Modeling Leaking Gas Plume Migration

In this study, we obtain simple estimates of 1-D plume propagation velocity taking into account the density and viscosity contrast between CO{sub 2} and brine. Application of the Buckley-Leverett model to describe buoyancy-driven countercurrent flow of two immiscible phases leads to a transparent theory predicting the evolution of the plume. We obtain that the plume does not migrate upward like a gas bubble in bulk water. Rather, it stretches upward until it reaches a seal or until the fluids become immobile. A simple formula requiring no complex numerical calculations describes the velocity of plume propagation. This solution is a simplification of a more comprehensive theory of countercurrent plume migration that does not lend itself to a simple analytical solution (Silin et al., 2006). The range of applicability of the simplified solution is assessed and provided. This work is motivated by the growing interest in injecting carbon dioxide into deep geological formations as a means of avoiding its atmospheric emissions and consequent global warming. One of the potential problems associated with the geologic method of sequestration is leakage of CO{sub 2} from the underground storage reservoir into sources of drinking water. Ideally, the injected green-house gases will stay in the injection …
Date: August 20, 2007
Creator: Silin, Dmitriy; Patzek, Tad & Benson, Sally M.
Object Type: Article
System: The UNT Digital Library
On Yang--Mills Theories with Chiral Matter at Strong Coupling (open access)

On Yang--Mills Theories with Chiral Matter at Strong Coupling

Strong coupling dynamics of Yang-Mills theories with chiral fermion content remained largely elusive despite much effort over the years. In this work, we propose a dynamical framework in which we can address non-perturbative properties of chiral, non-supersymmetric gauge theories, in particular, chiral quiver theories on S{sub 1} x R{sub 3}. Double-trace deformations are used to stabilize the center-symmetric vacuum. This allows one to smoothly connect smaller(S{sub 1}) to larger(S{sub 1}) physics (R{sub 4} is the limiting case) where the double-trace deformations are switched off. In particular, occurrence of the mass gap in the gauge sector and linear confinement due to bions are analytically demonstrated. We find the pattern of the chiral symmetry realization which depends on the structure of the ring operators, a novel class of topological excitations. The deformed chiral theory, unlike the undeformed one, satisfies volume independence down to arbitrarily small volumes (a working Eguchi-Kawai reduction) in the large N limit. This equivalence, may open new perspectives on strong coupling chiral gauge theories on R{sub 4}.
Date: August 20, 2008
Creator: Shifman, M.; /Minnesota U., Theor. Phys. Inst. /Saclay, SPhT; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept.
Object Type: Article
System: The UNT Digital Library
Materials Science at the Extremes of Pressure and Strain Rate (open access)

Materials Science at the Extremes of Pressure and Strain Rate

Solid state experiments at very high pressures and strain rates are possible on high power laser facilities, albeit over brief intervals of time and spatial small scales. A new shockless drive has been developed on the Omega laser. VISAR measurements establish the high strain rates, 10{sup 7}-10{sup 8} s{sup -1}. Solid-state strength is inferred using the Rayleigh-Taylor instability as a ''diagnostic''. Temperature and compression in polycrystalline samples can be deduced from EXAFS measurements. Lattice response can be inferred from time-resolved x-ray diffraction. Deformation mechanisms can be identified by examining recovered samples. We will briefly review this new area of laser-based materials science research, then present a path forward for carrying these solid-state experiments to much higher pressures, P >> 1 Mbar, on the NIF laser facility.
Date: August 20, 2003
Creator: Remington, B. A.; Cavallo, R. M.; Edwards, M. J.; Lasinski, B. F.; Lorenz, K. T.; Lorenzana, H. E. et al.
Object Type: Article
System: The UNT Digital Library
Formation of Pu amorphous alloys or metastable structures in Pu-Fe, Pu-Ta, and Pu-Si alloys (open access)

Formation of Pu amorphous alloys or metastable structures in Pu-Fe, Pu-Ta, and Pu-Si alloys

Sputter deposition technique was used to study the possible formation of amorphous structures in Pu-Fe, Pu-Ta, and Pu-Si systems. A triode sputtering system was used to prepare sputtered coatings: 13 to 59 at. % (a/o) Fe, 10 to 50 a/o Si, and 15 to 65 a/o Ta. Structure of the coatings was determined by x-ray diffraction techniques. The temperature stability of the obtained structures was determined by Differential Scanning Calorimetry (DSC) measurements. The Pu-Fe and Pu-Si binary systems showed strong evidence for the formation of amorphous phases in the sputtered coatings. X-ray analyses indicated the presence of Pu6Fe in the 13 to 20 a/o Fe range of Pu-Fe alloys and no apparent crystalline phases over the entire 10 to 50 a/o Si range of Pu-Si alloys. In the Pu-Ta system, the DSC data obtained for compositions below 50 a/o Ta did not show typical crystallization exotherms. At compositions above 50 a/o Ta, a metastable bcc alpha Ta structure was observed with an expanded lattice parameter. The calculated volume expansion (2.9%) corresponds to 29 a/o of Pu in solid solution if the lattice parameter is assumed to follow Vegards Law. After storage in a nitrogen glovebox atmosphere for over two years, …
Date: August 20, 1985
Creator: Rizzo, H.F. & Echeverria, A.W.
Object Type: Article
System: The UNT Digital Library